Abstract
Hydrogen recovery from CO 2/H 2 reformate mixtures by selective electrochemical pumping was compared from carbon supported Pt and Pd catalysts. Catalyst coated membranes were prepared by air-brushing a suspension of commercially available 20 wt% Pt/C or 20 wt% Pd/C catalysts and solubilized Nafion in methanol onto Nafion 115 membranes. Electrochemical activity and separation efficiency for the different catalyst layer formulations were evaluated by cyclic voltammetry, polarization and potentiostatic hydrogen pumping. The effective membrane-electrode-assembly (MEA) resistance increased due to dilution of H 2 by CO 2; the effective MEA resistance was greater for Pd/C catalysts than for Pt/C catalysts. CO 2 adsorbed more strongly to Pd catalysts than Pt catalysts reducing the electrochemical active surface area available for hydrogen oxidation/reduction. Pd/C catalysts had an energy efficiency for hydrogen recovery from reformate mixtures approximately 80% that of Pt catalysts. Because Pd is ten times less costly than Pt the results presented here suggest that Pd/C catalysts would be a promising candidate for hydrogen pumps to recover H 2 from reformate mixtures.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 424-434 |
| Number of pages | 11 |
| Journal | Journal of Power Sources |
| Volume | 218 |
| DOIs | |
| State | Published - Nov 15 2012 |
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering
Keywords
- Electrocatalyst coated membranes
- Electrochemical separations
- Hydrogen purification